


I Just Can't Help Myself

by morganoconner



Category: Teen Wolf (TV)
Genre: Demonic Possession, Demonic Voyeurism, M/M
Language: English
Status: Completed
Published: 2012-08-31
Updated: 2012-08-31
Packaged: 2017-11-13 06:46:39
Rating: Explicit
Warnings: Underage
Chapters: 1
Words: 3,187
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/500651
Author URL: https://archiveofourown.org/users/morganoconner/pseuds/morganoconner
Summary: <blockquote class="userstuff">
              <p>"Stiles," the demon says. In his head, her voice sounds soft and sleepy, like she's just woken from a long nap. "I'm bored."</p>
            </blockquote>





	I Just Can't Help Myself

**Author's Note:**

> I blame this entire thing on the cold medication. And on maybemalapert, who is evil.
> 
> This is not the demon!Stiles fic you're looking for. No, really.
> 
> I'm so sorry.
> 
> Written for Round 1 of [](http://stop-drop-howl.livejournal.com/profile)[](http://stop-drop-howl.livejournal.com/)**stop-drop-howl** , for the prompt _easy as sin_.

Stiles is never exactly alone inside his own head, but sometimes, it's all too easy to forget that he's sharing space with someone – some _thing_ – else. He guesses it's because he's grown used to it, that other presence that slipped in so many years ago and made itself at home in his body. It tends to stay quiet, buried beneath his subconscious, silently observing but not really involving itself very often.

If the demon has a name of its own, Stiles never learned it. He calls it 'Babs' after his mom's favorite cartoon character, and because the demon has always seemed a lot more female to him than male, like gender is a thing that matters where it came from.

It – or she, Stiles guesses – was weak when she slipped in through the cracks, his anger and pain and fear and depression calling to her like a siren. It was just after his mom died, and maybe that's why he never fought the intrusion. The demon needed a place to hide and recover her strength, and he needed something to keep the pain at bay when it got so bad he couldn't breathe. It was a mutually beneficial thing, not at all the hostile takeover Stiles has since seen described in the Argent's bestiary.

And yeah, so maybe Babs hadn't left when she was strong enough, maybe she'd stayed nestled inside him for longer than either of them ever thought she would, but Stiles has never had a reason to push the issue. It's comforting when he thinks about it, knowing she's there. When he's at his lowest, he always has a reason to remember that he's not alone.

Of course, that was the logic before things like werewolves and kanimas and Gerard Argent. Before things got so crazy in his own head that he all but forgot his own name, let alone that extra presence inside him that usually stays so quiet. Maybe if he'd remembered Babs, maybe if he'd let himself open up and talk to her, it wouldn't have seemed so bad at the time.

Well, _c'est la vie_. Too late to do anything about it now, and six months after the fact is _really_ no time to be dwelling on it. But Babs is in his head suddenly, right in the middle of his eleventh grade Chem class, whispering to him, and it's the first time he's actively thought about her in what feels like ages. The last time she'd actually spoken to him, Derek had just become an alpha, and she was scared he'd figure them out.

Despite that, Stiles can still remember her appreciative purr as she'd looked the werewolf up and down with an uncomfortably admiring warmth he'd felt in his gut. (Uncomfortable because it maybe possibly mirrored the feelings he'd been trying really hard not to acknowledge, but that's neither here nor there.)

Now, his hands clench tight around the lab table, knuckles going white as he feels her _stretch_.

 _Stiles_ , she says. In his head, her voice sounds soft and sleepy, like she's just woken from a long nap. _I'm bored._

He grits his teeth as he feels her expand. His breathing deepens, and his leg, which has been bouncing frantically underneath the lab table, stills without his say-so. _Babs_ , he thinks, as loudly as he possibly can. _Can't you wait for a better time? Like, when I won't get grounded for cutting school?_

He can _feel_ her pout. His hands loosen their tight grip on the table, no matter how hard he tries to hold on. _I just want to have a little fun_ , she says. _Please?_

He sighs. _After Chemistry, or Harris will kill me._

She scoffs. _He could try._ But she subsides without anymore protest, and he gains back the use of his note-taking hand.

Still, his concentration is shot after that, too focused on the way she's coiled up like a cat ready to pounce. It's been a long time since she was this restless. Every once in a while, she asks for a day or two to use and abuse his body at will, and since it always gets returned to him in one piece and without any weird diseases, Stiles has never had much of an issue with it. Why should he? Normally, she asks right around the times when he doesn't _want_ to be there, when his skin feels too tight and too itchy around him.

Usually, it's right around his mom's birthday. Or the anniversary of her death. Because Babs knows, and Babs is a good friend.

But this isn't close to either one of those dates, so yeah, he's a little confused. But Babs doesn't ask for much, and she's been very quiet for a long time now, so he can understand the desire to let loose a little. Why the hell not, anyway? There's no practice today, and it's not like Scott will notice, all wrapped up in Allison again like the last several months never happened.

After class, he goes out to the parking lot and heads toward his trusty Jeep. Doesn't even make it halfway before he stumbles, one foot freezing in place as Babs grabs hold of one controlling tether. _The Porsche_ , she whispers, and Stiles groans.

"Are you nuts?" he asks aloud. He feels her caress inside him, the touch soft and seductive. His mouth snaps shut, and she says, _Aren't you just a tiny bit tempted?_

He stares across the lot at Jackson's baby, his precious, his symbol of all things manly and rich. _God, yes_ , he whimpers to her, and Babs is the worst influence ever, because he's walking towards it long before he's consciously aware that it's him taking his own steps.

 _There you go, sugar_ , she says, guiding his hand to the key hidden in his jeans pocket, and he doesn't even wonder about it, doesn't ask her when she had time to grab it off Jackson in the seconds they brushed against him in the hallway after class. He just gets in, jams the key into the ignition, and guns it before anyone can see.

And yeah, Babs knows what she's talking about, that's for sure. There's nothing like it, cruising with the windows down and the late autumn wind blasting right through the cobwebs school left in his brain. "Where do you want to go?" Stiles asks her, raising his voice loud enough that the wind can't steal it, even if she doesn't need the physical words to hear him.

He feels her grin, lets it slide over his own face as she unfurls again. In the moment it takes to blink, it's she who's drumming their fingers against the wheel, she who's reaching a hand out the window to surf the breeze. It's she who laughs their delight into the open air as they fly into a turn she executes perfectly despite the speed. _We're gonna go have some fun_ , she promises, and Stiles…

Stiles is just naïve enough not to question the non-answer.

>:)

"What are you doing here?" Derek asks when he opens the door.

Stiles makes a sound that might be a _meep_ inside his own head, but Babs doesn't pass that message along, and she doesn't bother giving Derek an answer, either. What she _does_ do is press a hand to Derek's chest and push him back into his apartment, following until she's far enough in that she can kick the door closed behind them.

 _What are you doing?_ Stiles demands.

 _You've been pining_ , she answers, shoving a silent, gaping Derek into one of the overstuffed chairs in his living room. That shouldn't even be possible, which Stiles thinks speaks volumes about how bewildered Derek actually is right now. Well, good. That makes two of them. _It's boring_ , Babs continues, _and I'm tired of it, so I'm fixing it._

 _Oh, God,_ Stiles moans. He'd cover his face with his hands if he could, but all he's currently capable of is being the silent observer as Babs drapes herself – drapes _him_ – over Derek's lap, winding her – _his_ – arms around the werewolf's neck and leaning in close.

Derek growls, which does things to Stiles' body that he doesn't think is part of Babs' influence at all. And oh, God, there's no way Derek is going to be able to miss _that_. "What is this?" Derek demands.

Babs doesn't answer, doesn't let Stiles answer either. She presses her – _his_ , damn it – nose right into the curve of Derek's neck, breathing in his scent. Stiles' hands clench around the cut of Derek's hips, and his mouth opens just a little, just enough to drag his teeth over the skin it's pressed against. Stiles moans again, silently, hears it echoed by Derek.

 _That's right, sugar_ , Babs says, sounding delighted. _Easy as sin, ain't it?_

There's no warning before her influence flows away like water. Stiles isn't prepared to suddenly have control again, and he sags like a puppet with its strings cut. Derek's arms come up around him, and he holds Stiles to him for a long moment while Stiles' heart races.

 _I hate you,_ he tells Babs, closing his eyes and nuzzling into Derek's collarbone so he won't have to face him.

 _No you don't,_ she sing-songs right back.

"Stiles." Derek's voice is low, rough like sandpaper, a counterbalance to the gentleness of his hand where it's stroking up and down Stiles' spine. "Look at me."

Stiles does, slowly, pulling away and opening his eyes wide to stare at Derek, who's watching him with an intensity that feels both familiar and all kinds of brand new. He swallows hard.

"What is this?" Derek asks again.

 _Easy as sin,_ Babs reminds him in a whisper, and maybe he isn't like her, maybe he's not good at just taking what he wants and rolling with it, but he can take a page out of her book and at least _try_. "Kiss me?" he asks Derek, and his voice miraculously doesn't tremble. He wants to beg, wishes he could outright demand, but this is who he is and what he's got, and all he can do is hope it's enough.

Derek stares at him for what feels like forever before he lifts one hand to the back of Stiles' head and drags him in. Stiles has never kissed anyone before, not really, and he thinks that's one of the reasons Babs dove back into the backseat when she did. He wants to shout at her for it, because he has _no clue_ what he's doing, but then Derek's lips are sliding over his, and it's the easiest thing in the world to open to him.

 _That's it,_ Babs praises as Derek licks into Stiles' mouth. _Go with the flow, babe._

Stiles makes a small sound (it's not a _whimper_ , thank you very much), and Derek groans, his hands clamping around Stiles' hips as he shoves himself up and bites down gently on Stiles' bottom lip, and oh, God, this is nothing and everything like Stiles always imagined, when he dared to _let_ himself imagine. He thrusts his tongue into Derek's mouth and grinds down, and it's almost instinct to roll his hips _just so_ , in a way that makes Derek pull away from his mouth with a whine and latch onto his neck.

Stiles tilts his head to give him more access, and it's the hottest thing in the world, Derek marking him like he _owns_ him, out of control and running on instinct just like Stiles is, only Derek's instincts are _werewolf_ instincts, which just adds a whole new level of _ohgodyesplease_ that Stiles thinks he should maybe question himself about when he has the time. Or maybe question Babs about, because it's probably her fault.

One hand lifts to the nape of Derek's neck, and his fingers curl into the thick hair there and tug. Stiles only realizes that it's Babs when Derek's hips thrust again, when his spine arches and he moans against Stiles' skin. Babs coos inside Stiles' head and withdraws again, and Stiles is left petting Derek, soothing the spot with tender fingers and gentler tugs that leave Derek whimpering.

Derek's fingers are clumsy when they find the hem of Stiles' t-shirt and lift, and Stiles only makes it more difficult when he doesn't want to relinquish his hold on Derek long enough to lift his arms. Derek growls, and his eyes flash (and dear _God_ that shouldn’t be so hot right now), and the shirt tears right down the middle and falls to the floor.

And okay, yeah, Derek maybe had the right idea, because he darts forward and his mouth immediately latches onto one of Stiles' nipples, and now it's all Stiles can do to hold on when he feels it like an electrical current beneath his skin. _Easy, tiger,_ Babs whispers, soothing him with a soft mental caress. His hands are latched onto Derek's shoulders, digging in hard enough to bruise, and he groans at the feel of fang against skin – not hard enough to pierce, just enough to feel. "Derek, _Derek_ , oh _fuck_ ," he gasps, and feels Derek's lips curve.

Who's supposed to be seducing who, here, anyway?

 _Haven't I taught you anything?_ Babs asks him. _If you want to be in charge, you have to take it. Own it._ So saying, she takes control of one of his hands, snakes it down Derek's chest and runs the fingers over the top of Derek's jeans. Derek's breath hitches as she fades into the background again, and Stiles is left fumbling at the button, unhooking it and grabbing for the zipper with a hastiness that definitely gives away his inexperience.

"Stiles," Derek moans, pressing his forehead against Stiles' collarbone.

Stiles grins a little, wiggling his fingers into Derek's pants, reaching down until he can cup the hard length of Derek's dick in his palm. "Guess whatever I'm doing, I must be doing right, huh?" he asks breathlessly, adding a silent _thank you_ to Babs. Derek is shaking, fine tremors running up and down his spine as he gasps Stiles' name again, as he looks up and his eyes flash that gorgeous alpha-red with his desperation. Stiles feels powerful in a way he's never felt before, and he squeezes gently just so he can hear the sounds that pour from Derek's throat when he does.

From the caverns within his mind, Babs is approving. _Good boy,_ she says. _That's very good, sugar._ Her praise feels like sunshine and rainbows, and also makes him want to, like, wag his nonexistent tail and roll around in it, but he doesn't tell her either of those things because she'll just make fun of him. A lot.

Instead, he watches as Derek follows his lead, pulling Stiles jeans apart and lifting him enough that he can shove them down and off. It's totally unfair that Stiles is the mostly naked one here, but it's really hard to care as much as he should when Derek is dipping a hand into his boxers and tugging his dick free and stroking and _oh, God, Jesus fucking Christ_ there's no way he's going to last very long here.

Stiles leans forward, biting down on Derek's t-shirt clad shoulder to ground himself as he matches Derek's pace and tries desperately not to come to soon, because he wants it to be together, and he doesn't care how cheesy it is. Babs spreads herself out inside him, warming him, giving him some measure of control as he thrusts harder into Derek's grip. _He's close, babe, he's so close. You don't have to hold on for long._

And that's good, because there's no way he can, even with her helping him. He tightens his grasp on Derek's cock just a little, just enough, and twists his wrist in a way that makes Derek howl against his skin.

Their mouths meet again in a clash of tongues and teeth and greed, and their hips thrust frantically in time with each other, and then one of them – Stiles is never sure who, later – growls, "Now, now, come _now_ ," and that's it. Stiles spills into Derek's hand, feels Derek come warm and wet over his, and they're left gasping into each other's mouths for a long time after as they slowly come down from the high.

Babs sighs appreciatively. _Mmm, okay, yeah, that was worth the wait._

 _I'll say,_ Stiles agrees, even though coherent thought is taking a whole lot of effort right now. He curls himself into Derek's hold, nuzzling into his neck even as Derek's arms come back up around him.

"Stiles," Derek rumbles.

"Derek," Stiles replies, his voice sounding small and far away to his own ears.

"We need to talk." Derek noses at his cheek until Stiles turns just enough to look up at him.

"Hmm?" he asks.

Derek watches him for a long moment before bending to press a hard kiss to Stiles' mouth. "If this is going to happen again, that demon friend of yours should probably know that I don't share well."

The sound Stiles makes this time is _definitely_ a _meep_. "You _knew?_ " he demands. He would probably be flailing if Derek's arms weren't wrapped around him like particularly possessive vines.

"You've always smelled a little like sulfur," Derek tells him, "But when the demon was closer to the surface, it got a lot stronger. Also, your eyes went black a couple times there." Well, that's definitely news to Stiles. He mentally glares at Babs as Derek continues, "I'm not an idiot. The only reason I let anything happen was because it gave up control when it really counted."

Inside his head, Babs is cackling. _Ooh, I knew I liked him for a reason!_

Stiles buries his face against Derek's chest, moaning. "She only did it because I –"

"I know," Derek says, petting him, saving him from having to admit his own complete and total lack of balls out loud. "But you're _mine_ , and she better understand that."

A shudder goes through Stiles, and he wriggles happily against Derek. "She knows." _Damn right I do, sugar,_ she says. "She's just sort of…leasing?" He's never really thought about their arrangement like that, but it works. "But Derek, I…" He swallows, curling up tighter into Derek's arms. "I'm definitely yours. She's cool with that."

"Fair enough," Derek says. He pauses thoughtfully. "I guess I kind of like the idea of someone watching your back when I can't." He says it begrudgingly, but it still comes out honest. And then his voice lowers to a growl when he says, "Think she can disappear for a while if I take you to bed and do this properly?"

Stiles grins. "I think she can probably be convinced."

She cackles. _Yeah, babe, I'll give you two some privacy. Just be sure to ask him about his knot before you get to the good stuff._

Stiles is left choking on his own breath, staring wide-eyed at Derek as she disappears into the deepest, darkest recesses of his mind again.

She is, without doubt, pure evil.


End file.
